PURPOSE: To illustrate inductive coupling using radio waves.
DESCRIPTION: Install the vertical transmitting antenna with a coupling loop to the transmitter. Hold the receiving antenna near and parallel to the transmitting antenna. Change the coupling between the oscillator loop and the antenna loop by rotating the antenna loop. Coupling between the transmitter and the transmitting antenna is greatest when the light bulb between the two halves of the dipole receiving antenna glows brightly. When the loops are perpendicular there is little coupling and the bulb dims. When the loops are close and parallel the coupling is greater and the antenna bulb glows brightly.
REFERENCES: (PIRA unknown.)
EQUIPMENT: Transmitter with 52cm antennas, coupling loop, receiver with 80cm antennas, stand and clamp.
SETUP TIME: 5 min.
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